She was a member of a family that had owned and operated a paper company. She was also the Mellischwuler (queen bee) of a hive of Mellifers that resided in the attics of her family home.

The hive targeted Serena Dunbrook, Camilla Gotleib, and Adalind Schade, who were lawyers working for the firm involved in the legal action that forced the paper company into bankruptcy. The hive killed Dunbrook and Gotleib, but while it was attacking Schade, Nick Burkhardt killed Wincroft, who whispered a warning to Nick with her last breath, "He's coming for you. Beware, it's close." Once she was dead, all the bees flying around in the equipment room in the basement of a hotel appeared to die as well.